Frost dates for Bates Creek #2, WY
At Bates Creek #2, the median last spring frost (32°F) is May 22 and the median first fall frost is Sep 26, for a typical growing season of 125 days. For a 90% chance that the last frost has passed, wait until Jun 6. Nearby ZIP codes are in USDA hardiness zone 5a.
- May 22Last spring frost (median)50% chance of 32°F after this date
- Jun 6Safer planting date10% chance of 32°F after this date
- Sep 26First fall frost (median)50% chance of 32°F by this date
- 125 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | May 20 | Jun 4 | Jun 20 |
| 32°F | May 8 | May 22 | Jun 6 |
| 28°F | Apr 26 | May 9 | May 23 |
| 24°F | Apr 12 | Apr 29 | May 13 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Sep 1 | Sep 15 | Sep 27 |
| 32°F | Sep 11 | Sep 26 | Oct 9 |
| 28°F | Sep 22 | Oct 5 | Oct 20 |
| 24°F | Sep 30 | Oct 15 | Oct 29 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 81 days | 102 days | 121 days |
| 32°F | 103 days | 125 days | 146 days |
| 28°F | 127 days | 148 days | 168 days |
| 24°F | 144 days | 168 days | 188 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 100% |
Closest ZIP codes (each is closer to another station)
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 82609 | 5a | -20 to -15°F | 22 km |
| 82644 | 5a | -20 to -15°F | 24 km |
| 82636 | 5a | -20 to -15°F | 28 km |
| 82604 | 5a | -20 to -15°F | 43 km |
| 82637 | 5a | -20 to -15°F | 44 km |
| 82601 | 5a | -20 to -15°F | 50 km |
| 82646 | 5a | -20 to -15°F | 52 km |
| 82327 | 5a | -20 to -15°F | 58 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00480552, at 42.6233, -106.3567, elevation 1842 m (6,042 ft).
- Data quality: Standard (24+ years of data), 26 years of freeze data.
- Average days per year at or below 32°F: 188.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Casper 1sw (26 km)
- Casper Wastewater Plant (27 km)
- Casper Natrona Co Airport (32 km)
- Shirley Basin (35 km)
- Pathfinder Dam (44 km)
- Leo 6 SW (63 km)
- Powder River #2 (69 km)
- Powder River (school) (69 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.